Electric switch for electric lamp sockets



ELECTRIC SWITCH FOR ELECTRIC LAMP SOCKETS Filed Dec. 2, 1931 2 Shee-ts=She et 1 Jan 14 1936 T. FINIZIE ET AL 2&27583 ELECTRIC SWITCH FORELECTRIC LAMP SOCKETS Filed Dec.

2 sheets-sheet 2 INVENTEH E TUMAN 'Flwlzalz GEEIFRGE HENRy ELWELLPatented Jan. 14, 1936 ATEN'E' OFICE ELECTRIC SWITCH FOR ELECTRIC LAlVIPSOCKETS Tomun Finizie and G eorge Henry Elwell. New

poration of Connecti cut Application December 2, 1931, Serial No.578,536

4 Claims.

Our invention relates to electric switches for electric lamp sockets.Electric lamp sockets having no provision for a switch element arenaturally of shorter axial length than sockets within which space isreserved for the insertion of a switch element. The socket containingthe improved switch however, although provided with a switch element,maintains the shorter length by means of pivotally mounting the switchelement upon the washer of insulation and within the cap of the socketshell. This arrangement readily presents the opportunity to employ apivotally mounted switch-bar adapted to swing to either of two positionsto close or open an electric current simultaneously at two places in thecircuit to render, upon an open circuit, the screw-shell and centercontacts of the lamp socket absolutely dead, thus providing a safetyfeature of novel character. Therefore the objects of the invention areto provide an electric switch element for a lamp socket within .whichthe space, usually reserved for a switch element, is eliminated; toprovide for an electric lamp socket a switch element mountable upon awasher of insulation material; to provide a safety switch elementoperable to simultaneously open or close an electric circuit at oppositepoles; and to provide a pull-chain switch element pivotally suspendedfrom, and operable in planes parallel to, a washer of insulation Withthese and other objects in view as may become apparent from the withindisclosures, the invention consists not only of the particular formherein pointed out and illustrated by the drawings, but readily admitsof certain modifications within the scopeof what hereinafter may beclaimed.

The character of the invention may be best understood by reference toone illustrative device embodying the invention and illustrated by theaccompanying drawings in which the Figure 1 is an upright elevation of alamp socket provided with the improved switch element; the Figure 2 is across-section of a lamp socket illustrating the improved switch element;the Figure 3 is a top view of a washer of insulation and parts supportedthereby; the Figure 4 is a bottom plan view of the Figure 3 rotated 186degrees about a vertical axis in the plane of the sheet of drawings; theFigure 5 is a top view of the switch-bar; the Figure 6 is a view of theoperating lever; the Figure 7 is an edge view of the separated parts ofthe switch element in the order of their suspended relation; the Figure8 is a bottom view of the washer of insulation, illustrating full anddotted line positions of the switch-bar; and the Figure 9 is a top viewof a second washer of insulation. 1

Referring more particularly to the drawings, the general structure ofthe electric lamp socket. as illustrated is somewhat of the usual formwherein there is employed the outer casing I having the enlarged portion2, removably attached to the nippled cap 3 by any desired means, such asfor instance the projections 4 and perforations 5, the enlarged portion2 of the casing I containing the fixed washer of insulation 6 supportingthe insulation sleeve 1, the screw-shell contact 8 and the centercontact 9. Thus far the structure is old, excepting that the enlargedportion 2 of the casing I is materially reduced in length as comparedwith that portion of the usual outer casing provided space therein forthe insertion of a switch element, the elimination of such space andconsequent shortening of the casing I therefore forming one of thefeatures of this invention. An important factor of this invention is themounting of an electric switch element upon the washer of insulation 6instead of upon a block of insulation material usually inserted withinthe socket between the washer 6 and the cap 3. While the switch elementthus mounted upon the washer 6 may be of any practical form, a preferredform as illustrated includes the post It axially suspended from thecenter of the washer 6 Within the cap 3. Surrounding the post it andmounted or formed upon the under side of the washer 6, in any desiredmanner, are the spaced spherical projections II. Upon the same side ofthe washer I; the conductive plates I2 and I3 are also fixedly mounted,each equidistant upon opposite sides of the'spherical projections II,the plate I2 being conductively connected with an arm I l 01" the flangeI5 of the screw-shell contact 8, by means of the metal rivet It, and theplate I3 being conductively connected with an arm II of the centercontact 9 by means of the metal rivet I8. In a plane parallel with thewasher 6 is the second washer of insulation l9 rigidly suspended fromthe washer 8 by means of the U-shaped brackets 20 and 2i, each rivetedto both washers 6 and I9 and providing line terminals to which linewires (not illustrated), each inserted into the cap 3 and through aperforation 22 of the washer I9, may be attached by means of the screws23 and 24, each bracket it and RI having an integral portion, 25 and 26,respectively, lying in the plane of the conductive plates I2 and I3, theportion 25 of the bracket 20 being spaced from the conductive plate I2and the portion 26 of the bracket 2! being spaced from the conductiveplate l3. The switch-bar 21 of insulation material is pivotally mountedupon the post l and the upper side of the bar 2? is provided, in anydesired manner, with the spherical projections 28 encircling the post H3and each spherical projection 28 engageable between sphericalprojections II of the washer 6. Carried by opposite extremities of theswitch-bar 21 are the conductive plates 29 and 35, the conductive plate29 being engageable, as illustrated by the Figure 2, with the conductiveplate l2 and the portion 25 of the bracket 20 to conductively bridge theplate l2 and the portion 25 and, simultaneously therewith, theconductive plate 33 is engageable with the conductive plate l3 and theportion 26 of the bracket 2! to conductively bridge the plate l3 and theportion 25, thus closing the circuit traceable from the line terminal atthe screw 23 through the bracket 20, the portion 25, the plate 29 of theswitch-bar 21, plate l2, the rivet l6, the arm ll of the flange IS, theflange l5, the screw-shell 8, the metal base 31 of the electric lampbulb 32, the lamp filament (not illustrated), the lamp center contact33, the center contact 9 of the electric lamp socket, the arm ll of thecenter contact 9, the rivet I8, the conductive plate l3, the conductiveplate 33 of the switch-bar 27, the portion 23 of the bracket 2|, thebracket 2|, and to the other line terminal at the screw 24. The underside of the switchbar 27 is provided, in any desired. manner, with asurface ratchet formation 34. The operating lever 35 also of insulationmaterial is pivotally mounted upon the post l3, and the upper side ofthe lever 35 is provided in any desired manner with a surface ratchetformation 36 adapted, when moved in one direction, to interlock with theratchet formation 34 and carry the switch-bar 21 a quarter turn. Acoiled spring 31, surrounding the post I0 and having one end attached tothe operating lever 35 and the opposite end attached to the washer is,serves as a compression spring to provide a tension for maintaining thelever 35 and the switch-bar 21 in an upwardly spring-pressed relation tothe washer 6, the spring 3? also providing a winding and unwindingtension to return the lever 35 to its normal at-rest position, thebracket 2| if desired, may serve as a stop for engagement by the lever35. The lever 35 is provided with the usual arcuate groove 38 withinwhich the chain 39 is mounted, the pulling of the chain 38 being adaptedto move. the lever 35, and hence the switch-bar 27 carried thereby, aquarter-turn against the tension of the spring 3'! which returns thelever 35 when released, while the switch-bar 21 remains in the advancedposition to which it is moved by reason of the interengagement of thespherical projections H and 28 axially maintained by the spring 31. Asthe lever 35 is thus advanced a quarter turn from the positionillustrated by the Figure 2 to the dotted position illustrated by theFigure 8, the spherical formations 38 of the switch-bar 2'! suddenlyride up and over the spherical formations H of the washer 6 and againinterlocked but relatively advanced one step, the spherical formations23 and H thus providing a cam 'movement to suddenly separate theconductively engaging plates 29 and 33 from the plate and portion 12 andand from the plate and portion l3 and 23, respectively, thussimultaneously opening the circuit in both lines leading to theirrespective poles. A further quarter turn of the lever 35 likewisecarries the switch bar 21 to again contact its plates 29 and 30 with theplates and portions !2-25 and [3-26, respectively, to simultaneouslyclose both lines of the electric circuit.

We claim:

1. A switch element for an electric lamp socket having a casingcomprising interlocked cap and shell members, a washer of insulationheld between the interlocked cap and shell, screw-shell and centercontacts supported by the shell side of said washer, the switch elementbeing mounted upon the opposite side of said washer and wholly withinsaid cap member, the switch element including two fixed pairs of spacedmetal plates, the plates of one pair being conductively connected, onewith the screw-shell contact and the other with a line terminal, and theplates of the other pair being conductively connected, one with thecenter contact and the other with a second line terminal, and apivotally operable switch bar of insulation material having a conductiveplate upon each of its extremities and adapted to conductively bridgeeach pair of said fixed plates to close both lines of an electriccircuit.

2. A switch element for an electric lamp socket having a casingcomprising interlocked cap and shell members; a washer of insulationheld between the interlocked casing members; screwshell and centercontacts supported by the shell side of said washer and two pairs offixedly spaced contacts provided by the cap side of said washer, thescrew-shell and center contacts each having a conductive connection withone of each of said pairs of contacts, the other of each pair ofcontacts being connected with a line terminal, said switch elementincluding a springpressed axially yielding switch-bar of insulationmaterial and pivotally mounted upon said washer and within said cap formovement in a plane parallel to that of said washer, said switch-barhaving conductive extremities, each adapted to bridge a pair ofcontacts, and means adapted, upon the rotation of said switch-bar, tosuddenly engage or disengage said conductive extremities with said pairsof contacts to open or close a circuit.

3. A switch element for an electric lamp socket having a casingcomprising interlocked cap and shell members; a washer of insulationheld between the interlocked casing members; screwshell and centercontacts supported by the shell side of said washer, and two pairs offixedly spaced contacts provided in a common plane by the cap side ofsaid Washer, the screw-shell and center contacts each having conductiveconnection with one of each of said pairs of contacts, I

the other of each pair of contacts being connected with a line terminal,said switch element including a spring-pressed axially yieldingswitch-bar of insulation pivotally mounted upon said washer and withinsaid cap member for movement in a plane parallel to that of said washer,said switch-bar having conductive extremities, each adapted to bridge apair of contacts; fixed spaced cam-faced obstacles with which saidwasher is provided in the path of other spaced cameiaced obstaclescarried by said switch-bar, and means adapted to rotate the axiallyyielding switch-bar over said obstacles to thereby suddenly engage ordisengage said conductive extremities with said pairs of contacts toclose or open a circuit.

4. A switch element for an electric lamp socket comprising a suitablecasing enclosing insulation material having opposite surfaces andsupporting upon one surface screw-shell and center contacts and upon theother surface a switch element including in a common plane two fixedpairs of spaced metal plates, the plates of one pair being conductivelyconnected, one with the screw-shell contact and the other with a lineterminal, and the plates of the other pair being conductively connected,one with the center contact and the other with a second line terminal; aspring-pressed axially yielding switch-bar of insulation rotatablymounted upon a post supported by the enclosed insulation material, saidswitch-bar having conductive extremities; fixedly spaced cam-surfacedobstacles provided by the enclosed insulation material in the path ofother cam-surfaced obstacles carried by said switch-bar, and apull-chain mechanism adapted to rotate the axially yielding switch-barover said obstacles thereby suddenly raising and dropping the switch-barto disengage and engage said conductive extremities 10 with said fixedpairs of metal plates to open and close a circuit.

TOMUN FINIZIE.

GEORGE HENRY ELWELL.

